Eye Candy
The left eye....something strange is going on here..
Alright, not so much candy as it is special effects.. involving the eye. Horrible pun, I admit, but the effect is still interesting to watch considering the relative simplicity involved in this special effects/compositing test. The video at the end of the article will show off the final result.
Using Blender (and, for the first time, compositing nodes), I hand tracked the movement of my eye from some video footage taken using my laptop’s built in webcam at the decent resolution of 960 by 540. The footage was taken while in a moving vehicle, for some added difficulty. Composited over top of the eye is a false retina, which has been animated to match the combined movement of the camera, my head, and my eye. Now that the eye has been tracked I can make any changes or additions to the eye that I want, given some time and effort.
The basic layout I used while working on the Eye Test.
In this example, I created a circular psuedo sphere and placed it over the eye to simulate a retina, then tracked it to the outline of my real retina throughout almost every frame. While the effect is largely imperfect up close, when the video is rendered out to about half the full resolution it doesn’t look bad at all. With a lot of nitpicking and optimization, the hand tracking could come very close to approximating the true movement of the eye.
While animating the false retina, I also created two shapes that would loosely match the eyelids, so that I could make the retina disappear realistically when I close my eye. I did the same thing for a few frames near the end of the video, as my finger covered the view of my eye.
Though the last thing to really mention in this post, one of the first things I did was set up the compositing nodes, as this was done on the remainder of the car ride. I had to fiddle around at first, getting used to how they worked, but in the end the node setup looked something like in the picture posted above.
The movie images were fed in sequence after being exported from iMovie, and connected to an alpha over of the 3D Blender scene after it went through a blur filter. The end effect looked something like this.
Cheers!
–Lace